Missing colon after an object key
A key followed directly by its value with no colon separating them.
The input
{"a" 1}{"a": 1}How to fix it
Insert a colon between the key and the value.
Frequently a typo where the colon was typed as a semicolon, which reads almost identically at a glance.
What each parser reports
Every message below was captured by running this exact input through the parser named. 21 of 21 parsers rejected it.
| Parser | Exact message |
|---|---|
| CPython json.loads CPython 3.12.3 | Expecting ':' delimiter: line 1 column 6 (char 5)what this message means → |
| encoding/json Unmarshal Go go1.22.2 | invalid character '1' after object keywhat this message means → |
| Gson Java 21.0.12 | Expected ':' at line 1 column 7 path $.awhat this message means → |
| Gson JsonParser (lenient off) Java 21.0.12 | Expected ':' at line 1 column 7 path $.awhat this message means → |
| hjson Node.js 22.22.2 | Expected ':' instead of '1' at line 1,5 >>>"a" 1} ...what this message means → |
| Jackson ObjectMapper Java 21.0.12 | Unexpected character ('1' (code 49)): was expecting a colon to separate field name and valuewhat this message means → |
| JavaScriptCore JSON.parse JavaScriptCore (Bun 1.4.1) | JSON Parse error: Expected ':' before value in object property definitionwhat this message means → |
| json-bigint Node.js 22.22.2 | Expected ':' instead of '1'what this message means → |
| JSON5 Node.js 22.22.2 | JSON5: invalid character '1' at 1:6what this message means → |
| JSON::PP Perl 5.038002 | ':' expected, at character offset 5 (before "1}")what this message means → |
| json_decode PHP 8.3.6 | Syntax error |
| Newtonsoft.Json JsonConvert Newtonsoft.Json 13.0.3 on .NET 8.0.30 | Invalid character after parsing property name. Expected ':' but got: 1. Path '', line 1, position 5.what this message means → |
| Newtonsoft.Json JsonTextReader Newtonsoft.Json 13.0.3 on .NET 8.0.30 | Invalid character after parsing property name. Expected ':' but got: 1. Path '', line 1, position 5.what this message means → |
| orjson CPython 3.12.3 | unexpected character, expected ':' after key: line 1 column 6 (char 5)what this message means → |
| Ruby JSON.parse Ruby 3.2.3 | unexpected token at '{"a" 1}' |
| serde_json::from_str Rust (serde_json 1.x) | expected `:` at line 1 column 6what this message means → |
| SpiderMonkey JSON.parse SpiderMonkey 115 | JSON.parse: expected ':' after property name in object at line 1 column 6 of the JSON datawhat this message means → |
| System.Text.Json Deserialize .NET 8.0.30 | '1' is invalid after a property name. Expected a ':'. Path: $ | LineNumber: 0 | BytePositionInLine: 5.what this message means → |
| System.Text.Json JsonDocument .NET 8.0.30 | '1' is invalid after a property name. Expected a ':'. LineNumber: 0 | BytePositionInLine: 5.what this message means → |
| ujson CPython 3.12.3 | No ':' found when decoding object valuewhat this message means → |
| V8 JSON.parse Node.js 22.22.2 | Expected ':' after property name in JSON at position 5 (line 1 column 6)what this message means → |
What the specification says
The exact sections that govern this error. Descriptions are our paraphrase; follow the links for the normative text.
| Body | Section |
|---|---|
| IETF | An object is curly brackets around zero or more members. A name is a string, a single colon separates name from value, and a single comma separates a value from a following name. |
| Ecma International | Gives the object grammar and states that the syntax does not require name strings to be unique and assigns no significance to member ordering. |
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